[SOLVED] mencoder: how to keep audio bitrate setting at 192 kbps

Ehtetur · 11-25-2010, 03:38 PM

I need some help with mencoder settings... I'm doing a simple transcoding of an avi file from FFmpeg MPEG4 codec to XVID MPEG-4 codec.
The problem is that the audio bitrate is changing from 192 kbps to 32 kbps. The audio codec for both files is mp3 (MPEG-1 layer 3).

(I'm transcoding the FFmpeg MPEG4 encoded avi because my blu-ray player doesn't see, let alone play it. Any XVID MPEG-4 encoded avi files the blu-ray player sees and plays fine).

I ran mencoder trying the four settings below but the audio bitrate still comes out at 32 kbps:

Code:

mencoder camping_en.avi -ovc xvid  -oac mp3lame -xvidencopts bitrate=192 -o camping_us.avi
mencoder camping_en.avi -ovc xvid  -oac mp3lame -xvidencopts bitrate=687 -o camping_us.avi
mencoder camping_en.avi -ovc xvid  -oac mp3lame -xvidencopts bitrate=9146 -o camping_us.avi
mencoder camping_en.avi -ovc xvid  -oac mp3lame -xvidencopts bitrate=192000 -o camping_us.avi << OK, this was a WTF, but I'm desperate!

Anyone have an idea how to keep the bitrate at 192 kbps?

neonsignal · 11-25-2010, 03:51 PM

Your settings are changing the video bitrate, not the audio bitrate.

To set the audio bitrate, use the flag '-lameopts cbr:br=192' (constant bit rate, bit rate 192kpbs). The mencoder man page should have some examples.

Incidentally, you may not need to reencode both the video and audio streams (depending on what the player can handle). You can use the '-vcodec copy' and '-acodec copy' flags to just copy the streams.

Ehtetur · 11-25-2010, 03:59 PM

Quote:

Originally Posted by neonsignal

Your settings are changing the video bitrate, not the audio bitrate.

To set the audio bitrate, use the flag '-lameopts cbr:br=192' (constant bit rate, bit rate 192kpbs). The mencoder man page should have some examples.

Thanks neonsignal, that did it! =)